[填空题]
Consider the sequenc*hobs2;4)mw 4l,( x cntomc -lwmgfx1e cit ,tf.x t;a:$u_1$ , $u_2$ , $u_3$ , ... , $u_n$ , ... where
$u_1$=860, $u_2$=980, $u_3$=1100, $u_4$=1220.
The sequence continues in the same manner.
1.Find the value of $u_{50}$.
$u_{50}$= .
2.Find the sum of the first 10 terms of the sequence.
$S_{10}$= .
Now consider the sequence $v_1$ , $v_2$ , $v_3$ , ... , $v_n$ , ... where
$v_1$=2, $v_2$=4, $v_3$=8, $v_4$=16.
This sequence continues in the same manner.
3.Find the exact value of $v_{13}$.
$v_{13}$= .
4.Find the sum of the first 10 terms of this sequence.
$S_{10}$= .
k is the smallest value of n for which $v_n$ is greater than $u_n$.
