Someone help pleasee. Andre was trying to write 7^4/7^-3 with a single exponent and worte 7^4/7^-3 = 7^4 = 7^1 explain to Andre what his mistake was and what the answer should be.

1. whats 2/3 plus 1/9 2. 5/7 plus 1/2 3.7/15 plus 2/15

Determine the number of outcomes in the event. decide whether the event is a simple event or not. upper a computer is used to select randomly a number between 1 and 9 comma inclusive. event upper b is selecting a number greater than 4. event upper b has nothing outcome(s). is the event a simple event? (yes or no) because event upper b has (fewer than, exactly, more than) one outcome.

In a right triangle δabc, the length of leg ac = 5 ft and the hypotenuse ab = 13 ft. find: b the length of the angle bisector of angle ∠a.