1/8
Each time the probability for landing on heads in 1/2 or 50% so do 1/2*1/2*1/2=1/8.
Answer: Option 'c' is correct.
Step-by-step explanation:
Since we have given that
Probability that they were left handed P(L)= 40%
Probability that they were Democrats P(D)= 47%
So, P(L∩D) = 135 = 0.13
Now, to check whether they are independent or not.
We will find P(L) × P(D) is given by

Since P(L) . P(D) ≠ P(L∩D)
So, they are not independent.
Hence, Option 'c' is correct.
1.326 grams of NH3 are required to produce 4.65 g of HF.
Step-by-step explanation:
Balanced chemical reaction is written first to know the number of moles taking part in original reaction.
NH3 +3 F2 ⇒3 HF + NF3
Given:
mass of HF = 4.65
First the number of moles of HF in 4.65 grams is calculated by using the formula:
number of moles (n) = 
atomic mass of HF = 20 grams/mole
putting the values in the above equation number of moles can be found.
n = 
= 0.235 moles of HF are given.
From the equation it can be said that:
1 mole of NH3 reacts to form 3 moles of HF
so, x moles of NH3 would react to form 0.235 moles of HF
= 
3x = 0.235
x = 
x = 0.078 moles of NH3 is required.
The moles are converted to mass by applying the formula:
mass = atomic mass X number of moles (atomic mass of NH3 = 17 grams/mole)
putting the values in the formula
mass = 17 X 0.078
mass = 1.326 grams
Answer:
answer:250 pieces
1 metre=100cm so
10metres =100*10 =1000cm
each piece is 4 CM long, so.,
no. of pieces=1000/4
by dividing by 2....
=500/4
again by dividing by2...
=250/1=250 pieces
so 250 pieces of ribbon can be cuttted from 10 metre long ribbon.