Answer:
this might help
Explanation:
https://science.ksc.nasa.gov/mars/msp98/misc/MCO_MIB_Report.pdf
Answer:
See below
Explanation:
<u>Check One-Sample T-Interval Conditions</u>
Random Sample? √
Sample Size ≥30? √
Independent? √
Population Standard Deviation Unknown? √
<u>One-Sample T-Interval Information</u>
- Formula -->
- Sample Mean -->
- Critical Value -->
(given 
degrees of freedom at a 95% confidence level) - Sample Size -->
- Sample Standard Deviation -->
<u>Problem 1</u>
The critical t-value, as mentioned previously, would be , making the 95% confidence interval equal to 
This interval suggests that we are 95% confident that the true mean levels of lead in soil are between 381.5819 and 398.9181 parts per million (ppm), which satisfies the EPA's regulated maximum of 400 ppm.
Answer:
Advantages
The main advantage in the use of pulleys is that the effort becomes less as compared to the normal lifting of the weights. In other words, it reduces the amount of actual force required to lift heavy objects. It also changes the direction of the force applied. These two advantages in the use pulleys make them an important tool for heavy lifting. It also provides a mechanical advantage.
The other advantage in the use of pulleys is that the distance between the operator and weight. There is a safe distance between them which avoids any disaster. Pulleys are easy to assemble and cost-effective. The combination of different directional pulleys can change the position of the load with little effort. Though there are moving parts in the pulley system they require less or no lubrication after installation.
Disadvantages
Apart from the above-said advantages while using pulley systems, there are several disadvantages in their use. The main disadvantage in the use of the pulley system is that it requires large space to install and operate. The mechanical advantage of pulleys can go to higher values but need more space to install them.
In some cases, the ropes/belts move over the wheel with no grooves, the chances of the slip of ropes/belts from the wheel are inevitable. If the system is installed to use for a long time, they require maintenance and regular check-up of ropes/cables as the friction between the wheels and cables/ropes occur causing wear and tear to them. Continuous use of the system makes the ropes weak. The rope may break while using the system causing damages to the operator, surrounding place and the load which is being lifted.
