Answer:
1386cm^2.
Step-by-step explanation:
radius of circle=21cm
area of circle(a)=?
we know,
A=pi r^2
=22/7×(21)^2
=1386cm^2
Answer:
mean life = 8264.5 s
Step-by-step explanation:
k = - 0.000121
The relation is given by

Now, the mean life is the life time for which the sample retains.
The mean life is the reciprocal of the decay constant.
The relation between the mean life and the decay constant is

Answer:

Step-by-step explanation:
It's an arithmetic sequence.

The difference is constant.
The explicit formula of an arithmetic sequence:

Substitute:

<em>use distributive property</em>

I guess positive bcuz - -=+
Answer:
3.6 for tomatoes and 8.4 for lettuce
Step-by-step explanation:
70% of 12=8.4
30% of 12=3.6
check: 3.6+8.4=12