Suppose we want to put ourselves several years into the future on the earth and spend only one month of our own time doing it. We can accomplish this by taking a trip into space at high speed and returning again. It doesn't matter where we go. If we go fast enough, time on board the space craft will pass considerably more slowly than time on Earth. Find the speed at which we should travel so that one month on board the space craft will equal 11.0 years on Earth.

The velocity is  

Explanation:

In order to provide solution to this question we are going to be making use of the time dilation equation which is mathematically represented as

Where is the desired time to achieve the time travel which is give from the question as

 and   is the actual earth time which is given from the question as

 and c is the speed of light with a value of  

  and  v  is the speed we need to obtain

     Now making v the subject of the formula

Now substituting values

i think the answer is a, hope this is right, that would be my best guess.

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.