Can someone please explain how to code this problem?

Suppose Y1 is an object where > length(Y1) yields [1] 11 and mean (Y1) yields [1] 4.5. Suppose Y2 is an object where > length(Y2) yields [1] 8 and mean(Y2) yields [1] 2.3

If we assign > Y3 = c(Y1, 12, Y2, 9), then write the output for

a) > length (Y3)

b) > length (Y3)

Using R Studio.