Mrs. sullivan had 18 erasers at the end of the day. she remembered giving out 14 and getting back 11, then giving out 13 and getting back 14. how many erasers did she start with?

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

The base of a triangle is 8 1 3 meters and the height of the triangle is the fourth root of 16 meters meters. what is the area of the triangle?