Answer:
thank you
Step-by-step explanation:
The average speed would be 600 km/hr.
Step-by-step explanation:
Let the original speed be 'x'
Let the decreased speed be 'x-200'
Distance = 600 km
Time increased by 30 minutes
According to question, it becomes,

So, The average speed would be 600 km/hr.
Answer:
(D) Although cause-and-effect cannot be established, there is an association between stress and the presence of heart arrhythmias for the population of all women aged 30 to 50.
Step-by-step explanation:
Answer:
True
True
False
Step-by-step explanation:
TRUE
If the equation Ax = 0 has only the trivial solution, then A is row equivalent to the n × n identity matrix
Here's why
If the equation Ax = 0 has only the trivial solution the determinant of the matrix is NOT 0 and the matrix is invertible therefore it is row equivalent to the nxn identity matrix.
TRUE
If the columns of A span ℝ^n , then the columns are linearly independent
Here's why
Remember that the rank nullity theorem states that

According to the information given we know that

Therefore you have

and

Which is equivalent to the problem we just solved.
FALSE
If A is an n × n matrix, then the equation Ax = b has at least one solution for each b in ℝ^n
Here's why
Take b as a non null vector and A=0, then Ax = 0 and Ax=b will have no solution.
Speed= distance/time
So your distance is 36 miles and the time is 45 minutes. U convert the time to hours and you’ll get 0.75 hours.
Speed = 36/0.75
= 48 miles/hour