180-108= 172 172 divided by 5 is 14.4 z=14.4
180-67=113 y=113
Answer:
Prospective study
Step-by-step explanation:
<em>A cross-sectional study, also known as transverse study, is a type of observational study that analyzes data from a population at a specific point in time.</em> This kind of observation is used if cases cannot be identified a priori or if the prevalence of the disease or condition needs to be determined.
Cohort studies are when two or more groups of subjects are followed over time to see if they develop some disease or if some event occurs, there are two type of cohort studies, prospective and retrospective. <em>Prospective studies (or follow-up studies) follow subjects with different exposures until some point in time where something happens or the study ends</em>, r<em>etrospective studies use historical data</em> to make comparisons based on risk factors or exposures that occurred before the events.
Considering the information given and the observational study exposed to the question, we can conclude that we are talking about a prospective study because data is collected over the next 10 years.
I hope you find this information useful and interesting! Good luck!
Answer:
answer = 12.87 km/h
Step-by-step explanation:
Given
Ship A is sailing east at 25 km/h = 
ship B is sailing north at 20 km/h =
here x and y are the sailing at t = 4 : 00 pm for ship A and B respectively
so we get x = 4 ×25 =100 km/h
y = 4× 20 = 80 km/h
let z is the distance between the ships, we need to find
at t = 4 hr
At noon, ship A is 130 km west of ship B (12:00 pm)
so equation will be


derivative first equation w . r. to t we get



![\frac{dz}{dt} =\frac{1}{z}[(x -130)\frac{dx}{dt} +y\frac{dy}{dt}]](https://tex.z-dn.net/?f=%5Cfrac%7Bdz%7D%7Bdt%7D%20%3D%5Cfrac%7B1%7D%7Bz%7D%5B%28x%20-130%29%5Cfrac%7Bdx%7D%7Bdt%7D%20%2By%5Cfrac%7Bdy%7D%7Bdt%7D%5D)


Step-by-step explanation:
a. 6 £/hr
b. 6.8 £/hr.....is this right?
I believe the term is "constant".