Which are ways to improve the design of this experiment? Check all that apply.
Record data only at the very end to save time.
Experiment with a wider range of materials.
Use more legible handwriting when recording data.
Use a laboratory galvanometer to make precise measurements.
Test the strength of the electromagnet by varying the number of wire coils.

Currents in dc transmission lines can be 100 a or higher. some people are concerned that the electromagnetic fields from such lines near their homes could pose health dangers. for a line that has current 150 a and a height of 8.0 m above the ground, what magnetic field does the line produce at ground level? express your answer in teslas and as a percentage of the earth’s magnetic field, which is 0.50 g. is this value cause for worry?