PLS HELP I NEED THE ANSWER RN

The ratio of two numbers is 5 to 4. the sum of the numbers is 99. what number is the greater of the two numbers?

Which expression is equivalent to (4x^3*y^5)(3x^5*y)^2 \a) 24x^13*y^7b) 36x^13*y^7c) 36x^28*y^7d) 144x^16*y^12

In simplified exponential notation, the expression a^2•a^-3•a 1/a 0