Help me please. For these problems I need to solve for x and find the measures of the angles given I’m so stumped on these 3

:malik received a $300 gift card from his grandparents and is using it only to pay for his karate lessons, which cost $30 per month. determine what amount, in dollars, remains on the card after 8 months.

The perimeter of the rectangle is 120 feet. if the length of the rectangle is ten feet more than the width ,what are the dimensions (length and width) of the rectangle?

Ef is a median of trapezoid abcd. the length of ab is 12, and the length of cd is 18. the length of bf is 4. what is the length of fc?