Answer: 70 ft
Step-by-step explanation:
Given
height of book is measured by the function is

when the book is thrown 

The height of the book is 
Answer:
-4/5
Step-by-step explanation:
Answer:
Option C
Step-by-step explanation:
Given that u-ai + bj and v-ci + dj are vectors
We have dot product
hence inner product of u and v. So option a is true
The dot product of u and v is a scalar is true because dot product is always a scalar
The dot product of u and v is a vector. is false because dot product is only a scalar and has no direction and hence cannot be a vector
The dot product of u and v is given by the expression ac+bd
True because we multiply corresponding i components and j components and add.
So only C is not true.