need a complete soltion with steps

It is important to use the correct notation when answering this question. Remember to use the '___' notation for character and the "___" notation for strings otherwise this will result in a nil score Given p = _s"Maths For Computing", q =_s"is", r =_s"great" and s =_s"fun". Evaluate the following where possible. If you believe the expression to be invalid enter "I" as your response ASC(FIRST(r)) + _N FIRST(q) = N