Johnny ate a booger and it tasted like sugar, johnny wants to know who ate that booger..?

Does the problem involve permutations or? combinations? do not solve. the matching section of an exam has 4 questions and 7 possible answers. in how many different ways can a student answer the 4 ? questions, if none of the answer choices can be? repeated?

Cot(90° − x) = 1 the value of x that satisfies this equation is °. a. 60 b. 135 c. 225 d. 315

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25