The tallest building in the USA is Chicago Illinois it is 1450 ft talk how long would it take a penny to drop from the top of the building to the ground

Me what is the value of x? showing work would be appreciated - ! : )

In the following situation, determine whether you are asked to determine the number of permutations or combinations. then do the calculation how many ways are there to pick a starting five from a basketball team of twelve members? a. permutation; ps - 2520 b. combination; 1c, - 792 c. combination: 2cs - 2520 d. permutation; ps - 95040

Determine which expressions represent real numbers and which expressions represent complex number. asaaap! plis!