Instead of typing it all on here, I included my explanations with the work.
Answer:
No
Step-by-step explanation:
For a proportional relationship :
y = kx
Where , k = constant of proportionality
Taking the first set of data:
x = 50 ; y = 10
10 = 50k
k = 10/ 50 = 1/5
Hence, the proportional equation or relation is :
y = 1/5x
Check if this is true for other data points on the data :
Taking the second data point :
x = 85 ; check if y will be 20
From :
y = 1/5x
y = 1/5*85
y = 85/5
y = 17
Since ;
y value from the equation isn't the same as that in the table, then the table does not show a proportional relationship.
Answer:
B. 6.3%
Step-by-step explanation:
For each time that the coin is tosse, there are only two possible outcomes. Either it comes up tails, or it does not. The probability of coming up tails on a toss is independent of any other toss. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
Fair coin:
Equally as likely to come up heads or tails, so 
Probability that the first tails comes up on the 4th flip of the coin?
0 tails during the first three, which is P(X = 0) when n = 3.
Tails in the fourth, with probability 0.5. So



0.0625 * 100 = 6.25%
Rounding to the nearest tenth of a percent, the correct answer is:
B. 6.3%