Exercise Solutions: Booleans and Conditionals¶

1. Declare and initialize the following variables for our space shuttle.

   1let engineIndicatorLight = "red blinking";
   2let spaceSuitsOn = true;
   3let shuttleCabinReady = true;
   4let crewStatus = spaceSuitsOn && shuttleCabinReady;
   5let computerStatusCode = 200;
   6let shuttleSpeed = 15000;
   

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3. Write conditional expressions to satisfy the safety rules.

   1. 1if (crewStatus) {
      2   console.log("Crew Ready");
      3} else {
      4   console.log("Crew Not Ready");
      5}
      

   2. 1if (computerStatusCode === 200) {
      2   console.log("Please stand by. Computer is rebooting.");
      3} else if (computerStatusCode === 400) {
      4   console.log("Success! Computer online.");
      5} else {
      6   console.log("ALERT: Computer offline!");
      7}
      

   3. 1if (shuttleSpeed > 17500) {
      2   console.log("ALERT: Escape velocity reached!");
      3} else if (shuttleSpeed < 8000) {
      4   console.log("ALERT: Cannot maintain orbit!");
      5} else {
      6   console.log("Stable speed.");
      7}
      

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5. Monitor the shuttle's fuel status.

    1if (fuelLevel < 1000 || engineTemperature > 3500 || engineIndicatorLight === "red blinking") {
    2   console.log("ENGINE FAILURE IMMINENT!");
    3} else if (fuelLevel <= 5000 || engineTemperature > 2500) {
    4   console.log("Check fuel level. Engines running hot.");
    5} else if (fuelLevel > 20000 && engineTemperature <= 2500) {
    6   console.log("Full tank. Engines good.");
    7} else if (fuelLevel > 10000 && engineTemperature <= 2500) {
    8   console.log("Fuel level above 50%. Engines good.");
    9} else if (fuelLevel > 5000 && engineTemperature <= 2500) {
   10   console.log("Fuel level above 25%. Engines good.");
   11} else {
   12   console.log("Fuel and engine status pending...");
   13}
   

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