Need help ASAP rocky ! Help needed

Explain why the function is discontinuous at the given number a. (select all that apply.) f(x) = 1 x + 1 a = −1 f(−1) is undefined. lim x→−1+ f(x) and lim x→−1− f(x) exist, but are not equal. lim x→−1 f(x) does not exist. f(−1) and lim x→−1 f(x) exist, but are not equal. none of the above

Julius sold five times as many computers as sam sold last year. in total, they sold 78 computers. how many computers did julius sell?

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.