I will give brainy to whoever answers first and correct

5t

Step-by-step explanation:

f iv e

         An explicit formula designates the nth term of the sequence, as an expression of n (where n = the term's location).

          It defines the sequence as a formula in terms of n. It may be written in either subscript notation an n, or in functional notation, f (n). Sequence: {10, 15, 20, 25, 30, 35, ...}.

he spend 5.1 minutes chatting with his friends.

step-by-step explanation:

2/5+1/2=9/10

6/1-9/10=5.1