Can someone please help me on this question

Evaluate 4 a for a = 5 2/3 . express your answer in simplest form.

Mr switzer needs to buy new 1-foot tiles to cover his bathroom floor. the floor is 12 feet long and 8 feet wide. each square foot of tile will cost $1.79. in dollars what will be the total cost of the tiles he needs to buy.

The vertex of this parabola is at (-2,-3). when the x-value is -1, the y-value is -5. what is the coefficient of the squared expression in the parabola's equation?