What number is equivalent to 4 to 3 power

Emma will roll two number cubes labeled 1 through 6. she will record the sum of the two numbers after each roll. she will roll the two cubes 540 times. how many times should emma expect the sum to equal 5?

Ineeeeed this is due tomorrow and i dont know the answer can you find all the exponents

Write the expression 7x^3-28xy^2 as the product of 3 factors