Let 'x' be the distance from THE far bank where 700 is the distance to the NEAR bank
boat one has travelled 700 (rate = 700/unit time) boat two has travelled x rate = x / unit time
boat one then travels x + 400 more and boat two travels 700 + (700+x -400) more when they meet
The time is the same rate x time = distance distance/rate = time equate the distances divided by the respective rates
(700 + x + 400)/700 = ( x + 700 + (700+x-400) )/x
1100x + x^2 = 1400x + 700000
x^2-300x -700000 = 0 quadratic formula yields x = 1000
One boat travels 700 the other 1000 whe they first meet.....width of river = 700+ 1000 = 1700 m
Answer: 
Step-by-step explanation:
Given
Population of dust particle doubles every 30 minutes
If the initial sample is 21 grams
The model to predict the population will be

Where t=time in hours
A day has 24 hours . So, for 2 days time is 48 hours
Population is given by
Answer:
12
Step-by-step explanation:
Answer:
B and C
(I'm not sure if b and e are supposed to be the same though) if they are then, b, c, and e