Christopher is 20 years younger than ishaan. ishaan and christopher first met two years ago. fourteen years ago, ishaan was 3 times as old as christopher. how old is christopher now?

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Which of the following expressions is equal to 2x^2+8

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).