I have one small exercise in app inventor, but I can not do it. Who can help me build it. I'm very thankful for it 
Requirement :
Private investigators sometimes go into dangerous situations. This app will alert someone that the investigator may have come to harm by sending an SMS message. The idea is that before going into the dangerous situation the investigator uses the app to indicate the time at which a message should be sent. If the investigator doesn't use the app again to cancel the message before that time then the message will automatically be sent by the app.
Minimum requirements are:
? The investigator should be able to enter:
? The mobile number to which the SMS message is to be sent.
? The time at which the SMS message is to be sent. This can either be an actual time (e.g. 17.30) or time period after which the message will be sent (e.g. 30 mins)
? The investigator also needs a way to cancel the message if they do not wish it to be sent.
Possible additional features include:
? Allow the investigator to customise the message that is sent and/or choose from a range of pre-defined messages
? Choose the mobile number to which the message is to be sent to from the users' contacts
? Set a repeat for the message. For instance send a message every 10 minutes until cancelled. In order to test this the repeat time should be configurable.
Requirement :
Private investigators sometimes go into dangerous situations. This app will alert someone that the investigator may have come to harm by sending an SMS message. The idea is that before going into the dangerous situation the investigator uses the app to indicate the time at which a message should be sent. If the investigator doesn't use the app again to cancel the message before that time then the message will automatically be sent by the app.
Minimum requirements are:
? The investigator should be able to enter:
? The mobile number to which the SMS message is to be sent.
? The time at which the SMS message is to be sent. This can either be an actual time (e.g. 17.30) or time period after which the message will be sent (e.g. 30 mins)
? The investigator also needs a way to cancel the message if they do not wish it to be sent.
Possible additional features include:
? Allow the investigator to customise the message that is sent and/or choose from a range of pre-defined messages
? Choose the mobile number to which the message is to be sent to from the users' contacts
? Set a repeat for the message. For instance send a message every 10 minutes until cancelled. In order to test this the repeat time should be configurable.
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