While orbiting Mars, NASA's Mars Reconnaissance Orbiter took images of the planet's surface. In those pictures, lines, like plant
Vines, appeared to flow down from slopes on Mars. These lines showed up during the warmer seasons and disappeared in the colder
seasons. The discovery of the lines suggests that water exists on Mars.
Although Mars has long been known to have ice, researchers are sitting on pins and needles hoping more evidence will reveal itself
Water is an essential building block for life. Therefore, with this information, scientists think that finding life on Mars may be possible.
However, confirming the existence of water may take some time. Scientists have other missions already planned before they take on
finding water on Mars
Why are the lines on the slopes of Mars compared to plant vines?
A. to show how the lines spread across the slopes
B. to describe the harsh climate on the planet
c. to highlight the different varieties of plants
D. to explain how plants can survive on Mars

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation:

b is the answer.   i sat on the lumpy sofa, totally exhausted, with a bad taste in my mouth, wondering what i should do next.  

i would need to know the specific part of the passage your referring to ?