Answer
Sequence: $1,2,3,...,10$
Total number of trees planted: $55$
Work Step by Step
No. of trees in first row : $1$
No. of trees in second row : $2$
No. of trees in third row : $3$
.
.
.
No. of trees in 10th row : $10$
Sequence: $1,2,3,...,10$
Total number of trees planted:
$S_{10}=1+2+3+4+5+6+7+8+9+10$
$S_{10}= 55$
