Answer:
Average speed of car will be 48 km/hr
Explanation:
Let the total distance is 2d
It is given that first half of the distance car travels with a speed of 40 km/hr
So time taken to cover half of the distance 
Second half of the distance is covered with a 60 km/hr
So time taken to cover second half of the distance 
So total time to cover 2d distance 
Average speed is the ratio of total distance to total time
So average speed 
So average speed of car will be 48 km/hr
Answer:
X=m*g/K
Explanation:
Since the elastic force of the spring is balancing the force of gravity:
Fe = m*g
Now, on the spring by Hook's law, the magnitude of the elastic force will be:
Fe = K*X where K is the elastic constant of the spring and X is the distance the spring is strectches measured from its original lenght to its current length.
Replacing this value:
K*X = m*g Solving for X:
X = m*g/K This value is directly proportional to the object's weight and inversely proportional to the spring's constant.
Answer: The correct answer is : B. transduction
Explanation: Transduction is a process through which DNA is transferred from one bacterium to another through the action of a virus or a viral vector. There are two types of transduction, the generalized and the specialized. Transduction is a tool widely used by molecular biologists.
Answer:
distance changing at rate of 3.94 inches/sec
Explanation:
Given data
wall decreasing at a rate = 9 inches per second
ladder L = 152 inches
distance h = 61 inches
to find out
how fast is the distance changing
solution
we know that
h² + b² = L² ..................1
h² + b² = 152²
Apply here derivative w.r.t. time
2h dh/dt + 2b db/dt = 0
h dh/dt + b db/dt = 0
db/dt = - h/b × dh/dt .............2
and
we know
h = 61
so h² + b² = L²
61² + b² = 152²
b² = 19383
so b = 139.223
and we know dh/dt = -9 inch/sec
so from equation 2
db/dt = -61/139.223 (-9)
so
db/dt = 3.94 inches/sec
distance changing at rate of 3.94 inches/sec
