The project develops a "smart" heating thermostat. The control algorithms of the thermostat were modeled as Matlab/Simulink models and run on the internet connected server. The thermostat uses the specifications of the server to trigger the heating valves. The test manager has defined the following test strategy/approach in the test plan: 1. The acceptance test for the whole system is executed as an experience-based test. 2. The control algorithms on the server are tested during implementation using continuous integration. 3. The functional test of the thermostat is performed as risk-based testing. 4. The security tests of data / communication via the internet are executed together with external security experts. What four common types of test strategies/approaches did the test manager implement in the test plan?