(1) When using a 7-segment LED display to display the digit "4", which of the following LEDs must be lit (please circle one or more? Assume CA (common-anode) with a; b cd ef g (2) In a common-anode (CA) 7-segment LED display circuit below (assume no decimal point), if the anode is fixed at 5V, each LED has a 2V drop across it when it is lit (not counting the "point" segment, thus you have only 7 segment LEDs), what is the total current flows into the Arduino/ATmega328's pin when a digit "3" is displayed? The resistor in series with each LED is 1 k2. (hint: find the current flowing in cach them together). LE D-resistor branch, and then add (Problems (3) and (4) are from Page 4 in Lab 4 Manual) (3) Assuming that each LED has a 2V drop across it when it is lit, what is the maximum amount of current that will be sourced or sunk through each connected IO pin on the Arduino/ATmega328 when an LED segment is turned on? (Please look at the resistance value of an in-series current limiting resistor with an LED on the back of the board). (4) If every (16 total) segment is turned on at the same time, and the sum of all of these currents had to be sunk through the microcontroller simultaneously, what percentage of the total current able to be sourced/sunk by the ATmega328 would be consumed by just these LEDs (refer to the Absolute Maximum Ratings section of the ATmega328 datasheet)? (Refer to Appendix C and Appendix D of the Lab 4 manual, and answer the following questions) (5) Which Arduino library function is used to set up a pin's direction? If we want to set up Pin 5 to be INPUT, what is the corresponding code of the function? i.e., input or output) (Ans: pinMode(pin, direction) and pinMode(5, INPUT) (6) If we wanted to set up Pin 5 to be an INPUT pin using the PORTs DDRx (Data Direction Register) register, what is the appropriate bits should be (please use both binary and hexadecimal methods to express th register)? e bit status in the