If x=4 and y=2 what is the value of 5xy to the power of 2

Asailor is looking at a kite. if he is looking at the kite at an angle of elevation of 36and the distance from the boat to the point where the kite is directly overhead is 40 feet, how high is the kite?

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class