Two wires of the same material have resistances R1 and R2. The first wire has length L1 and diameter D1. The second wire has length L2 and diameter D2. Express R2/R1 in terms of L1, L2, D1, D2.

The resistance ($R$) of a wire is given by:

Where $\rho$ is the resistivity of the material, $L$ is the length of the wire, and $A$ is the cross-sectional area.

The cross-sectional area of a circular wire is $A = \pi r^2$, where $r$ is the radius. Since the diameter $D = 2r$, we have $r = D/2$.

Since both wires are made of the same material, their resistivity ($\rho$) is the same. The term $\frac{4\rho}{\pi}$ is constant for both wires.
Let $R_1, L_1, D_1$ be the resistance, length, and diameter of the first wire, and $R_2, L_2, D_2$ for the second wire.

Given:

• $L_1 = 20.0 \text{ m}$
• $D_1 = 1.50 \text{ mm}$
• $R_1 = 21.5 \Omega$
• $L_2 = 35.0 \text{ m}$
• $D_2 = 3.0 \text{ mm}$

Comparing this value to the options, $9.40625 \Omega$ is closest to $11.0 \Omega$.

The resistance of the second wire is approximately $\boxed{\text{d) } 11.0 \Omega}$.

Acceleration is the rate of change of velocity.

If an object moves with a constant velocity, it means its velocity is not changing. Therefore, the change in velocity ($\Delta v$) is zero.

Since $\Delta v = 0$, the acceleration ($a$) must be zero.

The acceleration of the object is $\boxed{\text{b) Zero}}$.

This means that if $d$ is distance and $t$ is time, then:

This can be written as $d = k t$, where $k$ is a constant of proportionality.

Velocity ($v$) is defined as the rate of change of distance with respect to time:

If $d = k t$, then differentiating with respect to time gives:

Since $k$ is a constant, the velocity ($v$) is constant.

An object moving with constant velocity is said to travel with constant speed (assuming the direction is also constant, which is implied by "distance covered" in a single direction).

The object is said to travel with $\boxed{\text{b) Constant speed}}$.