Người ta dùng một mặt phẳng nghiêng để kéo một vật có khối lượng 50 kg lên cao 2m. a. Nếu không có ma sát thì lực kéo là 125 N. Tính độ dài mặt phẳng nghiêng? b. Thực tế có ma sát và lực kéo là 175 N. Hiệu suất của mặt phẳng nghiêng dùng trên là bao nhiêu?

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Part I: Using the Colon Directions: Given below are sentences that require colons. Use the colon to correctly complete each sentence. Example: My mom said to her son “get home from school on time.” Answer: My mom said to her son: “get home from school on time.” 1. The man said it best “We are not afraid!” ______________________________________________________________________ 2. My dad hinted where the Easter egg was under the bushes. ______________________________________________________________________ 3. There was one thing left to do arrive with excitement. ______________________________________________________________________ 4. John spoke at the ceremony gallantly “We are all happy to be here.” ______________________________________________________________________ Part II: Listing with Colon Directions: Given below are sentences that require colons. Use the colon to correctly complete each sentence. 1. The bookstore specializes in three subjects art, architecture, and graphic design. ______________________________________________________________________ 2. David has the ingredients sugar, water, milk, and potatoes. ______________________________________________________________________ 3. I woke up at seven thirty a.m. in the morning. ______________________________________________________________________ 4. The school play includes five dances rumba, salsa, and samba. ______________________________________________________________________ Part III: Colons Introduce Quotation Directions: Re-Write each given sentence. Add a colon where necessary that indicates a quotation. Some sentences do not need a colon. Example: My mom said to her son: “get home from school on time.” 1. My dad told my brother “get your homework done.” ______________________________________________________________________ 2. Larry said to Sam “thanks for coming to dinner.” ______________________________________________________________________ 3. The woman spoke to the crowd “Everyone is equal” ______________________________________________________________________ 4. “What way are you going?” asked my friend. ______________________________________________________________________ Part IV: Writing Sentences with Colons Directions: Re-Write each given sentence. Add a colon where necessary that begins the explanation. 1. I went to the mall it was busy and filled with people. ______________________________________________________________________ ______________________________________________________________________ 2. The teacher gave out the directions no talking and listen quietly. ____________________________________________________________________________________________________________________________________________ 3. I brought my sports equipment to the gym a basketball shorts and water. ____________________________________________________________________________________________________________________________________________ 4. The food arrived at the table it was delicious and smelled good. ____________________________________________________________________________________________________________________________________________