Answer:
There are different phases of railroad expansion with the innovations in technology.
Explanation:
Few of the technological innovations are described below that leads in railroad expansion more rapid.
1. Centralized Traffic control (CTC) is introduced in 1960's that is used to control the traffic on railroads using different signal control.
2. In 1990's after computer technology involvement, railway ticket and reservation system is automate and being centralized. That makes the railroad expansion improve.
3. Bullet train technology has been introduced, that makes the railway trains more faster.
4. Electric trains has been introduced to use green energy and reduce the dependency on the fuel to make environment clean and green.
Answer:
the answer is
c. Trojan horses enter a secure space, while an infected file proceeds to be downloaded and run.
I think it’s number 1. Check the answer first.
Answer:
The function in python is as follows
def is_present(num,list):
stat = False
if num in list:
stat = True
return bool(stat)
Explanation:
This defines the function
def is_present(num,list):
This initializes a boolean variable to false
stat = False
If the integer number is present in the list
if num in list:
This boolean variable is updated to true
stat = True
This returns true or false
return bool(stat)