Answer:
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Please give brainliest
(s÷t) - r is the correct expression.
Answer:
0.2601
Step-by-step explanation:
There are 19C16 = 969 ways for Lester to choose 16 of the 19 objects.
There are 12C11 = 12 ways to choose 11 vases, and 7C5 = 21 ways to choose a non-vase, for a total of (12)(21) = 252 ways to choose exactly 11 vases in 16 objects.
So, the probability of interest is ...
252/969 ≈ 0.2601
_____
nCk = n!/(k!(n-k)!) ... the number of ways to choose k objects from n
4= 4.0
7/8= <span>0.875
Hope this helped!
</span>
Answer:
h = 8
Let the unknown number be h for height
V = LWH
984 = 20.5 x 6 x h
984 = 20.5 x 6h
984 = 123h
984 ÷ 123h
= 8
