Tooth fillings are often made of gold or porcelain because these materials are nonreactive.
b. nonreactive.
The spider will cross the driveway <u>25.71 in seconds</u>.
Why?
It's a conversion problem, so, in order to solve it, we need to convert the units of the given information.
Let's convert the given speed (in cm/s) to m/s.
We know that:

So, converting we have:

Then, calculating the time, we have:

We have that the spider will cross the driveway in 25.71 seconds.
Have a nice day!
Answer:

Explanation:
Given that

We know that acceleration a given as




We know that



So the magnitude of force F

The new period will be 2.486 days.
<h3>What is the period?</h3>
The period is found as the ratio of the angular displacement and the angular velocity. Its unit is the second and is denoted by t. The value of time needed to complete the rotation is the total period.
Given data;
Mass of a star,m= 1.210×10³¹ kg
The time period for one rotation of the star, T = 20.30 days
D' = 0.350 D
R' = 0.350 R
From the law of conservation of angular momentum;

Hence, the new period will be 2.486 days.
To learn more about the period, refer to the link;
brainly.com/question/569003
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