Ravish sold his motorcycle to Vineet at a loss of 28%. Vineet spent Rs 1680 on its repairs and sold the motorcycle to Rahul for Rs 35910, thereby making a profit of 12.5%, find the cost price of the motorcycle for ravish

Ijust need these 2 questions answered (the second pic is just confirmation i'm not confident in that answer)

Aresearch study is done to find the average age of all u.s. factory workers. the researchers asked every factory worker in ohio what their birth year is. this research is an example of a census survey convenience sample simple random sample

87.5% , 100% , 83.33 , 93.33% , 100% , 82.5% are all the academic points i've gotten this quarter. what's my final grade?