At a given instant of time two particles are having the position vectors `4 hati -4hatj + 7 hatk` metre and `2 hat i +2 hatj + 5hatk` respectively. If the velocity of the first particle be `0.4 hati ms^-1`, the velocity of second particle in metre per second if they collide after 10 s is

Explanation

To solve the problem, we need to find the velocity of the second particle (particle B) given the position vectors and the velocity of the first particle (particle A). Here are the steps to find the solution:

### Step 1: Identify the Position Vectors
The position vectors of the two particles are given as:
- Particle A: \( \vec{r_A} = 4 \hat{i} - 4 \hat{j} + 7 \hat{k} \) meters
- Particle B: \( \vec{r_B} = 2 \hat{i} + 2 \hat{j} + 5 \hat{k} \) meters

### Step 2: Calculate the Displacement Vector from B to A
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